1. Field of the Invention
This invention relates to metering pulse generators and more particularly to devices for installation on gas or water meters or the like to develop electrical pulses for transmission to a remote monitoring location. Metering pulse generators of the invention supply pulses of controlled amplitude and width, require a very low torque input, have minimal standby power requirements and a long operating life. The generators are quite compact and readily installed, are comparatively simple in construction and operation and are manufacturable at low cost.
2. Background of the Prior Art
Devices have heretofore been provided for developing pulses in response to rotation of dial arms of gas, water or other utility meters or the like. For example, the Sears U.S. Pat. No. 4,470,010 discloses an apparatus in which a dial arm of a meter engages a shoe which is affixed to one end of a shaft to rotate the shaft against the action of a coiled spring wrapped around the shaft. At its opposite end, the shaft has a striker arm portion which is engageable with a bar of piezoelectric material to generate an impulse. The impulse is transmitted through wires to remotely located circuitry. Many other types of metering pulse generators have been provided but the results obtained have been generally unsatisfactory and the devices have been complex, expensive and relatively large in size and not easily installed. A particular problem relates to energy consumption, particularly when the metering pulses are to be transmitted by devices designed for battery operation. For example, in devices designed to transmit metering data to a utility control center through a telephone line, it is desirable to use batteries to avoid the trouble, expense and possible hazards of obtaining power from an AC line. At the same time, it is desirable to minimize the expense of sending out service personnel to replace batteries and it is therefore desirable to minimize energy consumption and extend battery life as much as possible.